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  <element id="gldd_CompletedContractsMember" name="CompletedContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ContractsInProgressMember" name="ContractsInProgressMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_BasisOfPresentationLineItems" name="BasisOfPresentationLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_AccountsReceivableNoncurrentAndContractReceivableRetainage" name="AccountsReceivableNoncurrentAndContractReceivableRetainage" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_FuelHedgeContractsMember" name="FuelHedgeContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_PercentageOfCompletionAdjustment" name="PercentageOfCompletionAdjustment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
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  <element id="gldd_RevenueValueRemainingFromOutstandingPerformanceBonds" name="RevenueValueRemainingFromOutstandingPerformanceBonds" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
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  <element id="gldd_CasesPending" name="CasesPending" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <element id="gldd_DismissalCases" name="DismissalCases" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <element id="gldd_ActualCases" name="ActualCases" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_LineOfCreditFacilityOptionalIncreaseCapacity" name="LineOfCreditFacilityOptionalIncreaseCapacity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
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  <element id="gldd_SwinglineLoansMember" name="SwinglineLoansMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ScheduleOfCondensedConsolidatingOperationsAndComprehensiveIncomeTableTextBlock" name="ScheduleOfCondensedConsolidatingOperationsAndComprehensiveIncomeTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
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  <element id="gldd_IncomeLossFromEquityInvestmentsInSubsidiaries" name="IncomeLossFromEquityInvestmentsInSubsidiaries" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" name="IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
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  <element id="gldd_PaymentsForProceedsFromAccountsWithAffiliates" name="PaymentsForProceedsFromAccountsWithAffiliates" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_PaymentsOfDividendsShareBasedCompensation" name="PaymentsOfDividendsShareBasedCompensation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
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  <element id="gldd_InterestRateTypesAxis" name="InterestRateTypesAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_InterestRateTypesDomain" name="InterestRateTypesDomain" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
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  <element id="gldd_LiborRateMember" name="LiborRateMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_CostsAndEarningsForContractsInProgress" name="CostsAndEarningsForContractsInProgress" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
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  <element id="gldd_DerivativeUnderlyingHedgePercent" name="DerivativeUnderlyingHedgePercent" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <element id="gldd_GainLossOnAdjustmentOfContingentEarnout" name="GainLossOnAdjustmentOfContingentEarnout" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_CostsAndEarningsInExcessOfBillingsMember" name="CostsAndEarningsInExcessOfBillingsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
</schema>
</XBRL>
